The present invention relates to a plasma display apparatus (PDP apparatus) having an AC (alternating current) type plasma display panel (PDP). More particularly, the present invention relates to an ALIS system PDP apparatus which carries out an interlaced display in which every gap between neighboring sustain electrodes is utilized as a display line and odd-numbered display lines and even-numbered display lines are displayed alternately for each display frame.
The PDP apparatus using an AC type PDP is put to practical use and widely used as a thin large-screen display apparatus. Japanese Unexamined Patent Publication (Kokai) No. 9-160525 describes the ALIS system PDP apparatus in which the number of display lines is doubled without changing the number of electrodes. Japanese Unexamined Patent Publication (Kokai) No. 11-327503 has disclosed a configuration for an ALIS system PDP apparatus, which realizes a sustain driver for applying a sustain discharge voltage pulse to first electrodes (X electrodes) and second electrodes (Y electrodes) (referred to as sustain electrodes, altogether) by the use of a low maximum rating element. The present invention can be applied to the ALIS system PDP apparatus disclosed in Japanese Unexamined Patent Publication (Kokai) No. 9-160525 and Japanese Unexamined Patent Publication (Kokai) No. 11-327503.
FIG. 1 is a block diagram showing the outline of the ALIS system PDP apparatus disclosed in the above-mentioned Japanese Unexamined Patent Publication (Kokai) No. 11-327503. As shown in FIG. 1, a panel 1 is provided with first electrodes X and second electrodes Y extending in a first direction (transverse direction in this diagram) and spaced alternately, and address electrodes A extending in a second direction (longitudinal direction in this diagram) perpendicular to the first direction and arranged at identical intervals. In the ALIS system PDP apparatus, a display line is formed in every gap between neighboring X electrode and Y electrode. In other words, when 501 X electrodes and 500 Y electrodes are provided, a display line is formed between each Y electrode and one of its neighboring X electrodes, and between itself and the other neighboring electrode, that is, 1,000 display lines in total are formed. A display cell C is formed at the crossing of each display line (between X electrode and Y electrode) and the address electrode.
Each address electrode A is driven by an address driver 11 and a voltage pulse is applied independently of the address driver 11. Each X electrode is driven by a first (X) electrode drive circuit 12. The first electrode drive circuit 12 has an odd X sustain driver (X-odd) 13 and an even X sustain driver (X-even) 14. The odd-numbered X electrode is driven by the odd X sustain driver 13 and a sustain discharge pulse is applied at the time of sustain discharge. The even-numbered X electrode is driven by the even X sustain driver 14 and a sustain discharge pulse is applied at the time of sustain discharge. The phase of the sustain discharge pulse to be applied to the odd-numbered X electrode is opposite to that of the sustain discharge pulse to be applied to the even-numbered X electrode. Each Y electrode is driven by a second (Y) electrode drive circuit 15. The second electrode drive circuit 15 has a scan driver 16, an odd Y sustain driver (Y-odd) 17 and an even Y sustain driver (Y-even) 18. Each Y electrode is driven by the scan driver 16 and a scan pulse is applied sequentially at the time of addressing. At the time of sustain discharge, the odd Y sustain driver 17 applies a sustain discharge pulse to the odd-numbered Y electrode via the scan driver 16 and the even Y sustain driver 18 applies a sustain discharge pulse to the even-numbered Y electrode via the scan driver 16. The phase of the sustain discharge pulse to be applied to the odd-numbered Y electrode is opposite to that of the sustain discharge pulse to be applied to the even-numbered X electrode, and the phase of the sustain discharge pulse to be applied to the odd-numbered x electrode is the same as that of the sustain discharge pulse to be applied to the even-numbered Y electrode.
The sustain discharge pulse is a pulse of about 200V, and the phase of the sustain discharge pulse to be applied to the odd-numbered X electrode is opposite to that of the sustain discharge pulse to be applied to the even-numbered X electrode, and the phase of the sustain discharge pulse to be applied to the odd-numbered Y electrode is opposite to that of the sustain discharge pulse to be applied to the even-numbered Y electrode, therefore, as a result, a very large voltage is applied to each part of the drive element and it is necessary to use a high maximum rating element, if the odd X sustain driver 13 and the even X sustain driver 14 are integrated into one chip, or the scan driver 16, the odd Y sustain driver 17 and the even Y sustain driver 18 are integrated into one chip. Because of this, there arises a problem: the cost of the drive circuit is pushed up and a sufficient operation speed is difficult to obtain. To solve this problem, Japanese Unexamined Patent Publication (Kokai) No. 11-327503 has proposed that the scan driver 16 is divided into an odd scan driver for driving the odd-numbered Y electrode and an even scan driver for driving the even-numbered Y electrode, which are formed on separate chips, respectively, the odd Y sustain driver 17 and the even Y sustain driver 18 are formed on separate chips, respectively, and the odd X sustain driver 13 and the even X sustain driver 14 are formed on separate chips, respectively. In this manner, it is possible to reduce the voltage to be applied to the elements in a chip, and low maximum rating elements can be used.
As the ALIS system PDP apparatus shown in FIG. 1 is explained in detail in the above-mentioned Japanese Unexamined Patent (Kokai) No. 9-160525 and Japanese Unexamined Patent Publication (Kokai) No. 11-327503, no more detailed explanation is given here.
FIG. 2 is a diagram showing a layout when drive circuit parts relating to the X electrode and the Y electrode in the PDP apparatus shown in FIG. 1 are mounted. As shown schematically, on the left side of the panel 1 are provided the terminals of the X electrodes so that the X electrodes can be connected to the outside via connectors 41 and 42. Similarly, on the right side of the panel 1 are provided the terminals of the Y electrodes so that the Y electrodes can be connected to the outside via connectors 43 and 44. A circuit substrate 21 is provided with a sustain driver (X-odd) 22 for driving odd-numbered x electrodes and a sustain driver (X-even) 23 for driving even-numbered X electrodes, and a signal line 24 of the X-odd 22 and a signal line 25 of the X-even 23 are connected to the odd-numbered X electrodes and the even-numbered X electrodes via the connectors 41 and 42, respectively. As shown schematically, the panel 41 connects the X electrodes on the upper half side of the panel 1, the X electrodes including the odd-numbered and even-numbered X electrodes. Similarly, the connector 42 connects the X electrodes on the lower half side of the panel 1, the X electrodes including the odd-numbered and even-numbered x electrodes.
A circuit substrate 31 is provided with a plurality of scan driver elements 32 making up the scan driver 16, a sustain driver (Y-odd) 33 for driving the odd-numbered Y electrodes and a sustain driver (Y-even) 34 for driving the even-numbered Y electrodes. The plurality of scan driver elements 32 are divided into odd driver elements for driving the odd-numbered Y electrodes and even driver elements for driving the even-numbered Y electrodes, and the odd driver elements and the even driver elements are arranged alternately. A signal line 35 of the Y-odd 33 is connected to the odd driver elements and a signal line 36 of the Y-even 34 is connected to the even driver elements. The output lines of the odd driver elements and the even driver elements are connected to the corresponding odd-numbered Y electrodes and even-numbered Y electrodes via the connectors 43 and 44, respectively, in the order of the arrangement. Here, the four odd driver elements and the four even driver elements are provided, respectively, and the output lines of the two odd driver elements and the two even driver elements arranged on the upper half side in the figure are connected to the Y electrodes on the upper half side of the panel 1 via the connector 43. Similarly, the two odd driver elements and the two even driver elements arranged on the lower half side in the figure are connected to the Y electrodes on the lower half side of the panel 1 via the connector 44. The X-odd 22, the X-even 23, the Y-odd 33 and the Y-even 34 are realized by the use of elements having the same specifications.
As the drive circuit is provided on a circuit substrate different from the glass of the panel, a connector is required for connecting the output line of the drive circuit and the electrode terminal of the panel. As there are about 500 X electrodes and 500 Y electrodes, respectively, it is difficult to connect the X electrodes or Y electrodes with one connector, therefore, the X electrodes or the Y electrodes are divided into the upper half group and the lower half group and connected via two connectors.